I’ve seen a lot of those t-shirts and generally what is printed on them is the important part: a memorable hackathon, a cool product, etc. For an outsider, it’s often tricky to tell.
My favourite: the “I’ve done 100 interviews and the only thing I got was this t-shirt.” t-shirt at Facebook, with the 100 stroke-through to read 200. If looking really tattered, you know you are talking to someone who’s probably done a lot more interviews since the 200 mark. Expressly worn to show the candidate you know what you are talking about.
It was plain one and looked like he had spilled a burrito down it - he was also totally clueless about the role he was nominally recruiting for and seemed not to know any of the cool stuff AKQA had done
My favourite: the “I’ve done 100 interviews and the only thing I got was this t-shirt.” t-shirt at Facebook, with the 100 stroke-through to read 200. If looking really tattered, you know you are talking to someone who’s probably done a lot more interviews since the 200 mark. Expressly worn to show the candidate you know what you are talking about.